This invention generally relates to the manufacture of absorbent articles from absorbent material, and in particular to a splice connecting two portions of absorbent material which is useable in articles.
Personal care absorbent articles such as disposable diapers, training pants, other infant care products, other child care products, feminine napkins, panty liners, interlabial pads, other feminine care products, incontinence articles, and other adult care products have typically been manufactured using high-speed processing machines which have converted a stabilized web or ribbon of a fibrous absorbent material into an article. Each web has been pre-formed and provided to the machine as a wound roll or coil, in stacks of material, or blocks of connected or unconnected stacks of material. To prevent interruption of the processing machine a trailing end of each coil has been spliced to a leading end of the next coil. The resulting interconnected web has had sufficient tensile strength so that it may be provided to the machine and processed without breaking at the splice.
A drawback to conventional splicing techniques is that the splice has not been sufficiently liquid-permeable, and therefore, has been inadequate for use in an absorbent article. In the past, fibrous absorbent materials have been joined by an adhesive, or by an adhesive tape where the absorbent materials have not had sufficiently smooth surfaces which readily hold an adhesive. Adhesives and tape have been substantially impermeable to the liquids appointed for absorption. The adhesives and tape have hindered liquid from being absorbed by the absorbent structure of the article and have degraded the effectiveness of the article. In addition, the splices may be readily seen in the finished product, giving the perception of low quality. As a result, it is necessary to cull all spliced regions of the absorbent material, or to cull all articles that may have incorporated a portion of a spliced region. In practice, as many as seven articles have been culled per splice, producing a costly loss in efficiency and a costly waste of material.
Generally stated, a method aspect of the present invention can provide a process for splicing a first section of absorbent material to a second section of absorbent material to form a longer, continuous length of absorbent material suitable for a substantially uninterrupted sequential in-feed to a processing machine. The process includes a placing of a trailing end of a first portion of absorbent material in a position that substantially overlaps a leading end of a second portion of absorbent material to provide an overlapped splicing region. The trailing end of the first portion can be attached to the leading end of the second portion along at least a part of the overlapped splicing region with a thermal bond that provides a splice between the first portion of absorbent material and the second portion of absorbent material. In a particular feature, the trailing end of the first portion can be generally aligned with the leading end of the second portion. In another feature, the splice can have an operative tensile strength which is sufficient to support the sequential in-feed.
An article aspect of the invention can provide a substantially continuous length of absorbent material for a substantially uninterrupted sequential in-feed to a processing machine. The length of absorbent material can include a first portion of absorbent material having a trailing end, and a second portion of absorbent material having a leading end. The trailing end of the first portion of absorbent material can be placed in a position that substantially overlaps the leading end of the second portion of absorbent material to provide an overlapped splicing region, and in a particular feature, the trailing end of the first portion can be attached to the leading end of the second portion along at least a part of the overlapped splicing region with a thermal bond that provides a splice between the first portion of absorbent material and the second portion of absorbent material. In another feature, the splice can have an operative tensile strength which is sufficient to support a sequential in-feed to a processing operation. In a further feature, the leading end of the second portion of absorbent material can be generally aligned with the trailing end of the first portion of absorbent material
In another aspect, the invention can provide a personal care absorbent article having a spliced absorbent material. The article includes a liquid permeable bodyside liner for placement adjacent a wearer; and an absorbent core connected to the body side liner for absorbing liquid passing through the liner. The absorbent core includes a first portion of absorbent material, and a second portion of absorbent material. A trailing end of the first portion of absorbent material is placed in a position that substantially overlaps a leading end of the second portion of absorbent material to provide an overlapped splicing region. In a particular feature, the trailing end of the first portion can be attached to the leading end of the second portion along at least a part of the overlapped splicing region with a thermal bond that provides a splice between the first portion of absorbent material and the second portion of absorbent material. In another feature, the splice can have an operative tensile strength which is sufficient to support the sequential in-feed.
Additional aspects and features of the present invention are set forth in and are readily derived from the present disclosure.